This section provides background information related to the present disclosure which is not necessarily prior art.
A cooling cycle, air conditioning cycle, or refrigeration cycle typically includes a compressor, a condenser, an expansion valve assembly, and an evaporator. The cycle also includes a plurality of conduits (e.g., tubes or hoses) that fluidly connect the compressor, condenser, expansion valve assembly, and evaporator. A refrigerant flows through the conduits and through the compressor, condenser, expansion valve assembly, and evaporator cyclically, changing temperature and pressure through the cycle. Moreover, air flows past the evaporator to be cooled and absorb heat from an area. This cooled air can be used to cool a space (e.g., a passenger compartment of a vehicle). Also, air flows past the condenser to reject the heat that was absorbed in the evaporator.
Typically, the expansion valve assembly includes a diaphragm that deflects due to pressure and/or temperature of the refrigerant (e.g., due to pressure/temperature of refrigerant in dome or bulb that is in fluid communication with the low pressure suction portion of the system). The expansion valve can also include a moveable valve member that regulates flow through the expansion valve assembly. The diaphragm is coupled to the valve member such that deflection of the diaphragm causes the valve member to move and allow modulation. The amount of movement of the valve member (and, thus, the amount of movement of the diaphragm) is called a stroke or stroke distance.
The following discloses an apparatus and method of detecting the stroke distance conveniently and accurately. The following also discloses a method of testing a refrigeration cycle, wherein the stroke distance can be detectably varied, and operating conditions of the cooling cycle can be detected for each detected stroke distance.